/*
 * Copyright 2022 Netflix, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.mantisrx.runtime.core.functions;

/**
 *
 * A functional interface that defines a filter operation on a stream of
 * input elements of type {@code IN}.
 * @param <IN> the type of the input elements.
 */
@FunctionalInterface
public interface FilterFunction<IN> extends MantisFunction {
    /**
     *
     * Tests whether an input element should be included in the output stream.
     * @param in the input element.
     * @return {@code true} if the input element should be included in the
     * output stream, {@code false} otherwise.
     */
    boolean apply(IN in);
}
